The use of remote computing services, such as remote program execution and remote data storage, has greatly increased in recent years. Customers may reduce expenses and overhead by purchasing these services from a computing resource service provider (also referred to as a service provider). Customer applications may be distributed over multiple virtual machine instances and computing systems. The virtual machine instances may be controlled by a hypervisor operating on a computing system. The hypervisor may provide secure partitioning of computer system resources by executing multiple virtual machine instances on a single physical host machine. Various components of the hypervisor may require privileged access to the physical host machine in order to provide effective administration of the virtual machine instances. Although a particular type of hypervisor may support a variety of different applications and operating systems, certain features of the applications or operating systems may not be supported. Furthermore, customers may prefer a particular type of hypervisor or may have a preference between different types of hypervisors.